Best Way to prep surface for spoiler
 

Can't seem to find too much on this topic.

For a spoiler that is gonna be put on with the 3m double sided tape. What is the best way to prep the area for the adhesive?

I was going to wash the area with a mild dish soap, dry, claybar then rub the area with isopropyl alcohol.

Are there any other preferred methods? I'm reinstalling my spoiler so I want to assure that it's not gonna lift, like it did the first time lol.

Aside from cleaning the surface thoroughly I'll be using a heat gun to mold the spoiler to the trunk.

Any other tips would be good, unsure if adhesive promoter is necessary or not or where to get it.

Make sure the surface is stripped of any residue or wax. Other than that, pressure and a bit of heat can help the tape stick better. I've never had an issue w/ doing it this way.

I did all that you mentioned I also made sure the trunk was hot I just left the car in the sun

The adhesion promoter wipes they sell specifically for using 3m body molding tape... it is pretty much 90% isopropyl alcohol. After cleaning the area, removing wax run a cotton ball and the alcohol where the tape will be. Left it start to dry and then apply the tape/spoiler.